Twenty-six years ago, Lady Gaga was born this way in New York. But the pop star celebrated her 26th birthday on the West Coast -- and, by Gaga standards, it was a fairly chill celebration.

First on the agenda? A private spin class party at Soul Cycle's West Hollywood location. "She requested [Bruce Springsteen's] 'Thunder Road' because it's one of her favorite songs," a source tells Us Weekly. "Her friends filled the studio, and they had a blast."

For her birthday dinner, Gaga skipped the Los Angeles hot spots and opted instead for a low-key meal with her parents. "It was just a small thing with her family," the insider shares. "Her mother cooked."

Considering the singer's round-the-clock rehearsal schedule, it comes as no surprise that she'd want to take it easy on her special day. "She's been ridiculously busy, and has been working herself very, very hard" a Gaga pal tells Us. "But everyone had the most amazing time [yesterday]!"